Confinement in silicon nanowires: Optical properties

The blueshift of the optical absorption edge along with the intense red photoluminescence (PL) peak has been observed from micron-long crystalline silicon nanowires prepared by pulsed-laser vaporization of heated Si (mixed with metal catalyst) targets. Previous studies on the confinement in silicon nanostructures resulted in a dispute regarding the application of theoretical models to explain their optical properties. Based on the microstructure a phenomenological confinement model, incorporating the nanowire diameter distribution is used, which is found to describe the optical properties including the shape of absorption spectra, the band gap, and the PL peak position of the Si nanowires very well. (C) 2004 American Institute of Physics.